Which best describes how the people of harappan civilization were unique compared to those of the most other ancient civilizations?

They were not concerned with the afterlife.

they did not erect monuments
People of the Harappan civilization had stamp seals for signing their names, ceramics, bronze, copper, silver, gold, ivory, cotton and silk, running water and drains, brick houses, boats, and a port at Lothal in India. They had carnelian and agate beads and shell bangles, also.